Spedometer

My spedometer of my 98 sephia sometimes "flicks". I will be driving along and all of the sudden it is like I am in the Bramuda Triangle and it just goes crazy. It drops 15 mph, and then shoots up about 30 mph while the actual speed of the car remains constant. The engine is mechanically sound and no odd noises can be heard. Does anyone have any idea what the malfunction could be?

Engine doesn't effect how the speedometer works. The meter works off the wheel speed. Don't know how new cars work, but older cars have a direct cable to the dash cluster.

Check the back of the dash gauges to ensure nothing is loose.

Next step is to take it to the shop.

i had the same problem on mine. dealer wanted to replace the entire transmission. maybe i should have mentioned that i was a mechanic. i changed the vehicle speed sensor, its on top of the transmission, not too difficult to reach. cost 30 bucks at the dealer. hope this helps.

John

i had the same problem on mine. dealer wanted to replace the entire transmission. maybe i should have mentioned that i was a mechanic. i changed the vehicle speed sensor, its on top of the transmission, not too difficult to reach. cost 30 bucks at the dealer. hope this helps.

John


Cool, I'm having the same problem. I have replaced the speed sensor but that only helped for a few minutes of driving and now its right back to doing the same thing. Engine light on, O/D light flashing, speedometer jumping. We have it in at the shop getting the AC fixed which is costing about all we can afford at this point. Is there a conncetor that can malfunction? Is it the connector that plugs into the sensor? If not, where is the next most likely place I should look? If this isn't too difficult, I'd like to try and run it down myself. I am not a certified mechanic but I do most of my work on my old ford and older chevy and and have never goofed anything up. What I mean is I am very mechanically inclined.

My mechanic talked like he has to follow certain steps in the book and it could run into a lot of money I don't have. He did re-confirm the code was VSS related. I have no complaints about his work or rates and he is a good friend but when ya cannot budget the labor, sometimes ya have to look at other routes. Any advice to help us through this rough spot would be very appreciated (from anyone out there).

it could be a loose connection between vss-ecu or ecu-cluster. that's the only path it takes

Great, once it gets back from the AC repair, I'll check that. Just knowing there are no other connections in between narrows down the possibilities. The Evap Core had been leaking on the AC so I'm wondering if it and the ecu are located in close proximity of each other. Could the R-134 have leaked onto the connection somehow and corroded a wire connection. Thats what I will check first once I get the car back. Thanks.

B

very rare for that to happen they when the evap leaks it pretty much makes a mess in the box and the rest goes out the drain

Okay folks, I finally fixed the sucker. It was not the VSS. Its a different part that sits lower on the tranny called the spedo gear. It looks similar to the vss but has an actual gear on it. Its an easy fix and once the codes were cleared by taking off the battery terminal, they haven't come back and the car runs better than ever. Its a 40 dolllar part from Kia and it only took 18 months to get them to send the right one. I guess they finally realized I wasn't well-off enough to bring it in and felt sorry for me. Like this poor schmuck has been through enough, lets just send him the part already.